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Publications
Publications (51)
The Mirai botnet, composed primarily of embedded and IoT devices, took the Internet by storm in late 2016 when it overwhelmed several high-profile targets with massive distributed denial-of-service (DDoS) attacks. In this paper, we provide a seven-month retrospective analysis of Mirai's growth to a peak of 600k infections and a history of its DDoS...
The success of cloud computing has shown that the cost and convenience benefits of outsourcing infrastructure, platform, and software resources outweigh concerns about confidentiality. Still, many businesses and individuals resist moving private data to cloud providers due to intellectual property and privacy reasons. A recent wave of hardware virt...
In-browser cryptojacking is a form of resource abuse that leverages end-users' machines to mine cryptocurrency without obtaining the users' consent. In this paper, we design, implement, and evaluate Outguard, an automated cryptojacking detection system. We construct a large ground-truth dataset, extract several features using an instrumented web br...
Tor and I2P are well-known anonymity networks used by many individuals to protect their online privacy and anonymity. Tor's centralized directory services facilitate the understanding of the Tor network, as well as the measurement and visualization of its structure through the Tor Metrics project. In contrast, I2P does not rely on centralized direc...
Hardware Performance Counters (HPCs) have been available in processors for more than a decade. These counters can be used to monitor and measure events that occur at the CPU level. Modern processors provide hundreds of hardware events that can be monitored, and with each new processor architecture more are added. Yet, there has been little in the w...
Tor and I2P are well-known anonymity networks used by many individuals to protect their online privacy and anonymity. Tor's centralized directory services facilitate the understanding of the Tor network, as well as the measurement and visualization of its structure through the Tor Metrics project. In contrast, I2P does not rely on centralized direc...
Technical Support Scams (TSS), which combine online abuse with social engineering over the phone channel, have persisted despite several law enforcement actions. Although recent research has provided important insights into TSS, these scams have now evolved to exploit ubiquitously used online services such as search and sponsored advertisements ser...
Technical Support Scams (TSS), which combine online abuse with social engineering over the phone channel, have persisted despite several law enforcement actions. The tactics used by these scammers have evolved over time and they have targeted an ever increasing number of technology brands. Although recent research has provided insights into TSS, th...
Graph modeling allows numerous security problems to be tackled in a general way, however, little work has been done to understand their ability to withstand adversarial attacks. We design and evaluate two novel graph attacks against a state-of-the-art network-level, graph-based detection system. Our work highlights areas in adversarial machine lear...
Graph modeling allows numerous security problems to be tackled in a general way, however, little work has been done to understand their ability to withstand adversarial attacks. We design and evaluate two novel graph attacks against a state-of-the-art network-level, graph-based detection system. Our work highlights areas in adversarial machine lear...
Domain squatting is a common adversarial practice where attackers register domain names that are purposefully similar to popular domains. In this work, we study a specific type of domain squatting called "combosquatting," in which attackers register domains that combine a popular trademark with one or more phrases (e.g., betterfacebook[.]com, youtu...
Domain squatting is a common adversarial practice where attackers register domain names that are purposefully similar to popular domains. In this work, we study a specific type of domain squatting called "combosquatting," in which attackers register domains that combine a popular trademark with one or more phrases (e.g., betterfacebook[.]com, youtu...
Online advertising is a multi-billion dollar market, and therefore a target for abuse by Internet criminals. Prior work has shown millions of dollars of advertisers’ capital are lost due to ad abuse and focused on defense from the perspective of the end-host or the local network egress point. We investigate the potential of using public threat data...
Online advertising is a complex ecosystem that enables one of the most profitable businesses, which has become the target of abuse for Botnets. For example, recent charges filed from the United States Department of Justice against the operators of the DNSChanger botnet stated that the botnet stole at least $14 million [1, 2] from online advertisers...
An individual who re-registers an expired domain implicitly inherits the residual trust associated with the domain's prior use. Adversaries can, and increasingly do, exploit these ownership changes to undermine the security of both users and systems. In fact, many seemingly disparate security problems share a root cause in residual trust abuse. As...
Recent convergence of telephony with the Internet offers malicious actors the ability to craft cross-channel attacks that leverage both telephony and Internet resources. Bulk messaging services can be used to send unsolicited SMS messages to phone numbers. While the long-term properties of email spam tactics have been extensively studied, such beha...
Most modern cyber crime leverages the Domain Name System (DNS) to attain high levels of network agility and make detection of Internet abuse challenging. The majority of malware, which represent a key component of illicit Internet operations, are programmed to locate the IP address of their command-and-control (C&C) server through DNS lookups. To m...
In this article, we propose Segugio, a novel defense system that allows for efficiently tracking the occurrence of new malware-control domain names in very large ISP networks. Segugio passively monitors the DNS traffic to build a machine-domain bipartite graph representing who is querying what. After labeling nodes in this query behavior graph that...
Online advertising is a complex on-line business, which has become the target of abuse. Recent charges filed from the United States Department of Justice against the operators of the DNSChanger botnet stated that the botnet operators stole approximately US $14 million [11, 18] over two years. Using monetization tactics similar to DNSChanger, severa...
The edns-client-subnet (ECS) is a new extension for the Domain Name System (DNS) that delivers a “faster Internet” with the help of client-specific DNS answers. Under ECS, recursive DNS servers (recursives) provide client network address information to upstream authorities, permitting topologically localized answers for content delivery networks (C...
Devices infected with malicious software typically form botnet armies under the influence of one or more command and control (C&C) servers. The botnet problem reached such levels where federal law enforcement agencies have to step in and take actions against botnets by disrupting (or "taking down") their C&Cs, and thus their illicit operations. Lat...
Most modern malware download attacks occur via the browser, typically due to social engineering and drive-by downloads. In this paper, we study the " origin " of malware download attacks experienced by real network users, with the objective of improving malware down-load defenses. Specifically, we study the web paths followed by users who eventuall...
In this paper, we present an analysis of a new class of domain names: disposable domains. We observe that popular web applications, along with other Internet services, systematically use this new class of domain names. Disposable domains are likely generated automatically, characterized by a 'one-time use' pattern, and appear to be used as a way of...
Devices infected with malicious software typically form botnet armies under the influence of one or more command and control (C&C) servers. The botnet problem reached such levels where federal law enforcement agencies have to step in and take actions against botnets by disrupting (or "taking down") their C&Cs, and thus their illicit operations. Lat...
In this paper we study the structure of criminal networks, groups of related malicious infrastructures that work in concert to provide hosting for criminal activities. We develop a method to construct a graph of relationships between malicious hosts and identify the underlying criminal networks, using historic assignments in the DNS. We also develo...
In this paper, we present AMICO, a novel system for measuring and detecting malware downloads in live web traffic. AMICO learns to distinguish between malware and benign file downloads from the download behavior of the network users themselves. Given a labeled dataset of past benign and malware file downloads, AMICO learns a provenance classifier t...
Many botnet detection systems employ a blacklist of known command and control (C&C) domains to detect bots and block their traffic. Similar to signature-based virus detection, such a botnet detection approach is static because the blacklist is updated only after running an external (and often manual) process of domain discovery. As a response, botm...
In this paper we describe and evaluate a technique to improve the amount of information gained from dynamic malware analysis systems. By playing network games during analysis, we explore the behavior of malware when it believes its network resources are malfunctioning. This forces the malware to reveal its alternative plan to the analysis system re...
In recent years Internet miscreants have been leveraging the DNS to build malicious network infrastructures for malware command and control. In this paper we propose a novel detection system called Kopis for detecting malware-related domain names. Kopis passively monitors DNS traffic at the upper levels of the DNS hierarchy, and is able to accurate...
The Domain Name System (DNS) is an essential protocol used by both legitimate Internet applications and cyber attacks. For example, botnets rely on DNS to support agile command and control infrastructures. An effective way to disrupt these attacks is to place malicious domains on a "blocklist" (or "blacklist") or to add a filtering rule in a firewa...
Researchers have recently noted (14; 27) the potential of fast poisoning attacks against DNS servers, which allows attackers to easily manipulate records in open recursive DNS resolvers. A vendor-wide
upgrade mitigated but did not eliminate this attack. Further, existing DNS protection systems, including bailiwick-checking
(12) and IDS-style filtra...
Recently, a new attack for poisoning the cache of Recursive DNS (RDNS) resolvers was discovered and revealed to the public. In response, major DNS vendors released a patch to their software. However, the released patch does not completely protect DNS servers from cache poisoning attacks in a number of practical scenarios. DNSSEC seems to offer a de...
DNS implementers face numerous choices in architecting DNS resolvers, each with profound implications for security. Absent the use of DNSSEC, there are numerous interim tech-niques to improve DNS forgery resistance. We explore how different resolver architectures can affect the risk of DNS poi-soning. The contributions of this work include: (A) We...
We describe a novel, practical and simple technique to make DNS queries more resistant to poisoning attacks: mix the upper and lower case spelling of the domain name in the query. Fortuitously, almost all DNS authority servers preserve the mixed case encoding of the query in answer messages. Attackers hoping to poison a DNS cache must therefore gue...
In this paper we propose a solution to the DNS cache poisoning problem, which we called WSEC DNS (Wildcard Secure DNS). Our solution leverages existing properties of the DNS protocol and does not require any changes neither to the DNS protocol itself nor to the DNS resolution software run by nameservers. We propose to take advantage of the definiti...
